Address datagram review nits

Author: zerox80

quinn-proto/src/connection/datagrams.rs

@@ -32,10 +32,7 @@ impl Datagrams<'_> {
         let max = self
             .max_size()
             .ok_or(SendDatagramError::UnsupportedByPeer)?;
-        if data.len() > max {
-            return Err(SendDatagramError::TooLarge);
-        }
-        if data.len() > self.conn.config.datagram_send_buffer_size {
+        if data.len() > Ord::min(max, self.conn.config.datagram_send_buffer_size) {
             return Err(SendDatagramError::TooLarge);
         }
         if drop {
@@ -149,9 +146,11 @@ impl DatagramState {
     }
 
     fn has_send_buffer_space(&self, datagram_len: usize, send_buffer_size: usize) -> bool {
-        self.outgoing_total
-            .checked_add(datagram_len)
-            .is_some_and(|total| total <= send_buffer_size)
+        let Some(total) = self.outgoing_total.checked_add(datagram_len) else {
+            return false;
+        };
+
+        total <= send_buffer_size
     }
 
     /// Discard outgoing datagrams with a payload larger than `max_payload` bytes